--- /dev/null
+/*\r
+ * FreeRTOS Kernel V10.2.1\r
+ * Copyright (C) 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.\r
+ *\r
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of\r
+ * this software and associated documentation files (the "Software"), to deal in\r
+ * the Software without restriction, including without limitation the rights to\r
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of\r
+ * the Software, and to permit persons to whom the Software is furnished to do so,\r
+ * subject to the following conditions:\r
+ *\r
+ * The above copyright notice and this permission notice shall be included in all\r
+ * copies or substantial portions of the Software.\r
+ *\r
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR\r
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS\r
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR\r
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER\r
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN\r
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.\r
+ *\r
+ * http://www.FreeRTOS.org\r
+ * http://aws.amazon.com/freertos\r
+ *\r
+ * 1 tab == 4 spaces!\r
+ */\r
+\r
+/******************************************************************************\r
+ * NOTE 1: This project provides two demo applications. A simple blinky\r
+ * style project, and a more comprehensive test and demo application. The\r
+ * mainCREATE_SIMPLE_BLINKY_DEMO_ONLY setting in main.c is used to select\r
+ * between the two. See the notes on using mainCREATE_SIMPLE_BLINKY_DEMO_ONLY\r
+ * in main.c. This file implements the simply blinky style version.\r
+ *\r
+ * NOTE 2: This file only contains the source code that is specific to the\r
+ * basic demo. Generic functions, such FreeRTOS hook functions, and functions\r
+ * required to configure the hardware are defined in main.c.\r
+ ******************************************************************************\r
+ *\r
+ * main_blinky() creates one queue, and two tasks. It then starts the\r
+ * scheduler.\r
+ *\r
+ * The Queue Send Task:\r
+ * The queue send task is implemented by the prvQueueSendTask() function in\r
+ * this file. prvQueueSendTask() sits in a loop that causes it to repeatedly\r
+ * block for 1000 milliseconds, before sending the value 100 to the queue that\r
+ * was created within main_blinky(). Once the value is sent, the task loops\r
+ * back around to block for another 1000 milliseconds...and so on.\r
+ *\r
+ * The Queue Receive Task:\r
+ * The queue receive task is implemented by the prvQueueReceiveTask() function\r
+ * in this file. prvQueueReceiveTask() sits in a loop where it repeatedly\r
+ * blocks on attempts to read data from the queue that was created within\r
+ * main_blinky(). When data is received, the task checks the value of the\r
+ * data, and if the value equals the expected 100, writes 'Blink' to the UART\r
+ * (the UART is used in place of the LED to allow easy execution in QEMU). The\r
+ * 'block time' parameter passed to the queue receive function specifies that\r
+ * the task should be held in the Blocked state indefinitely to wait for data to\r
+ * be available on the queue. The queue receive task will only leave the\r
+ * Blocked state when the queue send task writes to the queue. As the queue\r
+ * send task writes to the queue every 1000 milliseconds, the queue receive\r
+ * task leaves the Blocked state every 1000 milliseconds, and therefore toggles\r
+ * the LED every 200 milliseconds.\r
+ */\r
+\r
+/* Standard includes. */\r
+#include <stdio.h>\r
+#include <string.h>\r
+\r
+/* Kernel includes. */\r
+#include "FreeRTOS.h"\r
+#include "task.h"\r
+#include "queue.h"\r
+\r
+/* Priorities used by the tasks. */\r
+#define mainQUEUE_RECEIVE_TASK_PRIORITY ( tskIDLE_PRIORITY + 2 )\r
+#define mainQUEUE_SEND_TASK_PRIORITY ( tskIDLE_PRIORITY + 1 )\r
+\r
+/* The rate at which data is sent to the queue. The 200ms value is converted\r
+to ticks using the pdMS_TO_TICKS() macro. */\r
+#define mainQUEUE_SEND_FREQUENCY_MS pdMS_TO_TICKS( 1000 )\r
+\r
+/* The maximum number items the queue can hold. The priority of the receiving\r
+task is above the priority of the sending task, so the receiving task will\r
+preempt the sending task and remove the queue items each time the sending task\r
+writes to the queue. Therefore the queue will never have more than one item in\r
+it at any time, and even with a queue length of 1, the sending task will never\r
+find the queue full. */\r
+#define mainQUEUE_LENGTH ( 1 )\r
+\r
+/*-----------------------------------------------------------*/\r
+\r
+/*\r
+ * Called by main when mainCREATE_SIMPLE_BLINKY_DEMO_ONLY is set to 1 in\r
+ * main.c.\r
+ */\r
+void main_blinky( void );\r
+\r
+/*\r
+ * The tasks as described in the comments at the top of this file.\r
+ */\r
+static void prvQueueReceiveTask( void *pvParameters );\r
+static void prvQueueSendTask( void *pvParameters );\r
+\r
+/*-----------------------------------------------------------*/\r
+\r
+/* The queue used by both tasks. */\r
+static QueueHandle_t xQueue = NULL;\r
+\r
+/*-----------------------------------------------------------*/\r
+\r
+void main_blinky( void )\r
+{\r
+ /* Create the queue. */\r
+ xQueue = xQueueCreate( mainQUEUE_LENGTH, sizeof( uint32_t ) );\r
+\r
+ if( xQueue != NULL )\r
+ {\r
+ /* Start the two tasks as described in the comments at the top of this\r
+ file. */\r
+ xTaskCreate( prvQueueReceiveTask, /* The function that implements the task. */\r
+ "Rx", /* The text name assigned to the task - for debug only as it is not used by the kernel. */\r
+ configMINIMAL_STACK_SIZE * 2U, /* The size of the stack to allocate to the task. */\r
+ NULL, /* The parameter passed to the task - not used in this case. */\r
+ mainQUEUE_RECEIVE_TASK_PRIORITY, /* The priority assigned to the task. */\r
+ NULL ); /* The task handle is not required, so NULL is passed. */\r
+\r
+ xTaskCreate( prvQueueSendTask, "TX", configMINIMAL_STACK_SIZE * 2U, NULL, mainQUEUE_SEND_TASK_PRIORITY, NULL );\r
+\r
+ /* Start the tasks and timer running. */\r
+ vTaskStartScheduler();\r
+ }\r
+\r
+ /* If all is well, the scheduler will now be running, and the following\r
+ line will never be reached. If the following line does execute, then\r
+ there was insufficient FreeRTOS heap memory available for the Idle and/or\r
+ timer tasks to be created. See the memory management section on the\r
+ FreeRTOS web site for more details on the FreeRTOS heap\r
+ http://www.freertos.org/a00111.html. */\r
+ for( ;; );\r
+}\r
+/*-----------------------------------------------------------*/\r
+\r
+static void prvQueueSendTask( void *pvParameters )\r
+{\r
+TickType_t xNextWakeTime;\r
+const unsigned long ulValueToSend = 100UL;\r
+BaseType_t xReturned;\r
+\r
+ /* Remove compiler warning about unused parameter. */\r
+ ( void ) pvParameters;\r
+\r
+ /* Initialise xNextWakeTime - this only needs to be done once. */\r
+ xNextWakeTime = xTaskGetTickCount();\r
+\r
+ for( ;; )\r
+ {\r
+ /* Place this task in the blocked state until it is time to run again. */\r
+ vTaskDelayUntil( &xNextWakeTime, mainQUEUE_SEND_FREQUENCY_MS );\r
+\r
+ /* Send to the queue - causing the queue receive task to unblock and\r
+ toggle the LED. 0 is used as the block time so the sending operation\r
+ will not block - it shouldn't need to block as the queue should always\r
+ be empty at this point in the code. */\r
+ xReturned = xQueueSend( xQueue, &ulValueToSend, 0U );\r
+ configASSERT( xReturned == pdPASS );\r
+ }\r
+}\r
+/*-----------------------------------------------------------*/\r
+\r
+static void prvQueueReceiveTask( void *pvParameters )\r
+{\r
+unsigned long ulReceivedValue;\r
+const unsigned long ulExpectedValue = 100UL;\r
+const char * const pcPassMessage = "Blink\r\n";\r
+const char * const pcFailMessage = "Unexpected value received\r\n";\r
+extern void vSendString( const char * const pcString );\r
+extern void vToggleLED( void );\r
+\r
+ /* Remove compiler warning about unused parameter. */\r
+ ( void ) pvParameters;\r
+\r
+ for( ;; )\r
+ {\r
+ /* Wait until something arrives in the queue - this task will block\r
+ indefinitely provided INCLUDE_vTaskSuspend is set to 1 in\r
+ FreeRTOSConfig.h. */\r
+ xQueueReceive( xQueue, &ulReceivedValue, portMAX_DELAY );\r
+\r
+ /* To get here something must have been received from the queue, but\r
+ is it the expected value? If it is, toggle the LED. */\r
+ if( ulReceivedValue == ulExpectedValue )\r
+ {\r
+ vSendString( pcPassMessage );\r
+ vToggleLED();\r
+ ulReceivedValue = 0U;\r
+ }\r
+ else\r
+ {\r
+ vSendString( pcFailMessage );\r
+ }\r
+ }\r
+}\r
+/*-----------------------------------------------------------*/\r
+\r
projects / freertos / blobdiff